Ballpoint pens refer to writing instruments that dispense oil-based ink using a small, revolving ball. Rollerball and gel pens use the same ball mechanism but are filled with liquid and gel-based ink instead of oil-based. "Ballpoint" and "ball pen" are occasionally used to refer to any pen with a rotating ball in the tip, but at JetPens, "ballpoint" only refers to oil-based ink pens. Some ballpoint pens are labeled as "emulsion," "hybrid," or "low-viscosity." These terms are used to describe ballpoint inks that are formulated to be runnier than traditional ballpoint pens. Learn more by reading our guides below: